What the biggest size wheels, I could put on an auto fastback w/out weakening performance even the slightest. What ever size, I'm gonna try to hunt down some lightweight wheels.
Also what size tires do you suggest I go with for the size wheels you suggested. ???/?? /??
ThanksChris
Will big wheels kill an automatic's performance
Okay out of the three tire measure ments (??/??/??)
Wich set of the numbers is the ouside diameter. I just now there's 3 measurments... I know the last is hte size of wheel the tire is for.
Does anyone know what stock size wheel is for fastbacks, or all s13 wheels same?
Thanks again for the infoChris
Wich set of the numbers is the ouside diameter. I just now there's 3 measurments... I know the last is hte size of wheel the tire is for.
Does anyone know what stock size wheel is for fastbacks, or all s13 wheels same?
Thanks again for the infoChris
Well, determining the OD is not that simple. You have to use all the numbers. The first number is the tire width. It tells you how wide the tire is in mm. The second number is called the aspect ratio. It uses the tire width to determine the height of the sidewall. The aspect ratio is a percentage. To find the sidewall height, you must multiply the percentage(aspect ratio) by the tire width, and you'll have the sidewall height in mm. Convert the side wall height to inches, multiply it by 2 and add it to the rim diameter and viola!: You have the O.D...
..or you can use the neat little calculator and forget doing the calculations by yourself: http://www.miata.net/garage/tirecalc.html
..or you can use the neat little calculator and forget doing the calculations by yourself: http://www.miata.net/garage/tirecalc.html
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Grant@tirerack
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The actual tire sizes will vary a bit even within the same size. It's not an exact formula but it will get you close. We list the tire specs on our website whenever they are available from the vendor including the O.D. :
http://www.tirerack.com/a.jsp?...x.jsp
http://www.tirerack.com/a.jsp?...x.jsp
This is a great topic to discuss...
I've found HOURS of reading material from a google search for "unsprung weight"
People may have heard different ratios for the unsprung-to-sprung weights. Others say there is no ratio, period.
The fact remains that unsprung weight is the enemy of wheel response(to include acceleration and BRAKING). You must also keep in mind that heavier wheels also contribute to accelerated wear on struts... Let's digress a little bit:
On average, a shock moves 10million times for every 20k miles driven. Heavier wheel/tire assy will stress suspension and increase shock(strut) oscillation, and premature wear is the end result.
Let's see what some other people think. Here's some finds from the google search:
For those interested, I weighed up a few of the unsprung weight items on mycar, while going through a brake upgrade. I was quite surprised at theweight difference between worn out solid stock rotors and brand new ventedrotors from Wilwood.
Front rotors excessivley used (way under spec) 14 lbsFront Caliper with worn pads 11 lbs8" Campy with BFG Euro T/A 225/50R15 37 lbs10" Campy with BFG Euro T/A 305/50R15 53 lbs
New wilwood vented brake rotors 14 lbsNew wilwood super lite calipers 7 lbsKinesis K5 w/ new BFG 245/35R17 g-force r1 47 lbsKinesis K5 w/ new BFG 315/35R17 g-force r1 53 lbs
you must read this linkhttp://victorylibrary.com/mopar/sprung-c.htm
http://www.toyo.com.au/tech_info6.htmlReducing unsprung weight improves the responsiveness of the vehicle's suspension system. A more responsive suspension system provides improved ride comfort, handling and grip. Passenger car manufacturers spend large amounts of development time & money reducing unsprung weight for this reason.
http://www.me.boun.edu.tr/sae/dat/sus/Unsprung weight transfer (WTU): In roll, weight transfer of unsprung weight is seperate for the front and rear suspensions of the race car. In a good design, it should only be a small component of TWT. But it is clear that a big change in the proportion of front vs rear unsprung weight will change the balance of the car.
http://www.tirerack.com/wheels/tech/perform.htmReduced Unsprung Weight Compared to Steel WheelsThis is one of the most critical factors affecting a vehicle's road holding ability. Unsprung weight is that portion of a vehicle that is not supported by the suspension (i.e. wheels, tires and brakes) and therefore most susceptible to road shock and cornering forces. By reducing unsprung weight, alloy wheels provide more precise steering input and improved "turning in" characteristics.
By reducing the weight of the vehicle's rotational mass, alloy wheels provide more responsive acceleration and braking
I've found HOURS of reading material from a google search for "unsprung weight"
People may have heard different ratios for the unsprung-to-sprung weights. Others say there is no ratio, period.
The fact remains that unsprung weight is the enemy of wheel response(to include acceleration and BRAKING). You must also keep in mind that heavier wheels also contribute to accelerated wear on struts... Let's digress a little bit:
On average, a shock moves 10million times for every 20k miles driven. Heavier wheel/tire assy will stress suspension and increase shock(strut) oscillation, and premature wear is the end result.
Let's see what some other people think. Here's some finds from the google search:
For those interested, I weighed up a few of the unsprung weight items on mycar, while going through a brake upgrade. I was quite surprised at theweight difference between worn out solid stock rotors and brand new ventedrotors from Wilwood.
Front rotors excessivley used (way under spec) 14 lbsFront Caliper with worn pads 11 lbs8" Campy with BFG Euro T/A 225/50R15 37 lbs10" Campy with BFG Euro T/A 305/50R15 53 lbs
New wilwood vented brake rotors 14 lbsNew wilwood super lite calipers 7 lbsKinesis K5 w/ new BFG 245/35R17 g-force r1 47 lbsKinesis K5 w/ new BFG 315/35R17 g-force r1 53 lbs
you must read this linkhttp://victorylibrary.com/mopar/sprung-c.htm
http://www.toyo.com.au/tech_info6.htmlReducing unsprung weight improves the responsiveness of the vehicle's suspension system. A more responsive suspension system provides improved ride comfort, handling and grip. Passenger car manufacturers spend large amounts of development time & money reducing unsprung weight for this reason.
http://www.me.boun.edu.tr/sae/dat/sus/Unsprung weight transfer (WTU): In roll, weight transfer of unsprung weight is seperate for the front and rear suspensions of the race car. In a good design, it should only be a small component of TWT. But it is clear that a big change in the proportion of front vs rear unsprung weight will change the balance of the car.
http://www.tirerack.com/wheels/tech/perform.htmReduced Unsprung Weight Compared to Steel WheelsThis is one of the most critical factors affecting a vehicle's road holding ability. Unsprung weight is that portion of a vehicle that is not supported by the suspension (i.e. wheels, tires and brakes) and therefore most susceptible to road shock and cornering forces. By reducing unsprung weight, alloy wheels provide more precise steering input and improved "turning in" characteristics.
By reducing the weight of the vehicle's rotational mass, alloy wheels provide more responsive acceleration and braking